There are risks associated with exposure to crystalline silica dust and quartz during roof tile cutting operations.

Silica is found naturally in sand, sandstone, granite, clay, shale, slate and various rocks and soils. Typical products which contain silica include concrete, mortar, clay bricks, calcium silicate bricks, and both concrete and terracotta roof tiles. It has become an increasingly common practice for roof tiling subcontractors to cut the edge of valley tiles using hand held power grinders in order to obtain acceptably straight edges. Often excess dust is then ‘blown’ off the surrounding roof.

The use of power tools for cutting roof tiles can generate high concentrations of very fine crystalline silica dust in this type of working environment.

Exposure to silica dust can cause irritation to the eyes, nose and throat like most other dusts, resulting in tearing, sneezing or coughing. However, inhalation of very fine (respirable) crystalline silica dust can also cause irreversible scarring of the lungs—a disease called silicosis.  Respirable refers to a particle size less than 7 microns that can enter the alveoli, deep in the lungs, and remain there to cause scarring.  Silicosis usually develops after inhalation exposure to relatively low concentrations of crystalline silica dust or quartz over a long period of time. Victims are likely to suffer severe shortness of breath and will find it difficult or impossible to walk even short distances. There is no medical treatment for silicosis. Once the disease has begun, it will continue to progress even if the worker is removed from further exposure. People with silicosis are also at greater risk of developing bronchitis and lung cancer. The risk of developing silicosis depends on many factors including the crystalline silica content of the material being worked with, particle size and concentration of silica in the dust, and the duration of exposure. The recommended national exposure standard for respirable crystalline silica or quartz is an 8 hour average of 0.1 mg/m³.

(WORKSAFE VICTORIA - SAFETY ALERT)

Safetyquip recommends the use of P2 Disposable Respirators as the very minimum in respiratory protection as P2 will capture particle sizes down to 0.3 microns (a human hair can average approx 50 microns in diameter).  Medium impact safety spectacles are not enough eye and face protection when using a grinder.  A faceshield should be the preferred choice.  Think about the cost to repair a broken tooth or a fractured cheek bone.  Safety spectacles obviously will not protect the cheek, nose, teeth or jaw.